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Science Log Two Debrief. Field Studies and Food Webs. Vocabulary. Species. A group of organisms that can mate and produce offspring that in turn can produce more offspring . Northern Cardinal- Cardinalis cardinalis. Vocabulary. extinct.
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Science Log Two Debrief Field Studies and Food Webs
Vocabulary • Species A group of organisms that can mate and produce offspring that in turn can produce more offspring Northern Cardinal- Cardinaliscardinalis
Vocabulary • extinct Condition in which there are no more living members of a species. Blue Pike- Sander vitreusglaucus
Vocabulary • mammals Animals that have fur or hair, usually give birth to live young, and can nurse their young with milk. Raccoon- Procyonlotor
Vocabulary • food web In an ecosystem, arrangement of several overlapping food chains.
Vocabulary • ecosystem All the living populations in an area along with the non living parts of an ecosystem. (Biotic and Abiotic)
Question 1 • 1. A school butterfly club did a field study to document the species of butterflies present in their Ohio town. Students divided a circular field study area into five sections. The students took photographs and recorded notes describing each section. Students always observed butterflies in the study area at the same time of day during the same four months of the year. Butterflies within 10 feet of the students were captured in nets, photographed for identification and then released. Data collected for four years are shown in the table. In 2002, the club reported to the North American Butterfly Association that the Striped Hairstreak butterfly was extinct. In their report, the students wrote that they suspected that the local pesticide spraying in 2000 was the cause of the extinction of this butterfly species. The students received a reply stating their conclusion was not scientifically valid. In your answer, give two reasons why the students’ conclusion was not scientifically valid. Striped Hairstreak- Satyriumliparops
Possible answers… • It takes TONS of census data to declare a species as EXTINCT. This data is only four years. (only 2 years with no sightings) • The declaration of EXTINCTION goes through TONS of government agencies. • The data is limited to one town in Ohio in a small sample area. The butterfly could be in other parts of the world. • Local pesticide spraying is NOT a large scale environmental change. • There is a LACK of definitive evidence that the pesticides actually killed the butterflies and were responsible for their decrease in numbers.
Question 2 2. Sea otters are marine mammals that live in giant kelp forests along the Pacific coast of North America. Sea otters have an important role in the food web of this ecosystem. When sea otters are removed from the giant kelp forest, the kelp also begins to disappear. In your answer, explain why the absence of sea otters would lead to a decrease in the giant kelp. Then, choose another organism in the food web and explain why the decreasing amount of giant kelp would affect that organism.
Possible Response • If there were no sea otters in the kelp forest, there would be more sea urchins. The larger than normal number of sea urchins would eat more kelp than usual and cause the kelp to decrease in abundance. The decrease in kelp could lead to a decrease in the number of snails because the snails would have less food. • This question focuses on removal of a predator from an ecosystem… which is BAD news.